Effect of parameter and sensing errors on DTC IM drive operation

The direct torque control (DTC) of an induction motor drive carries out the closed-loop control of the stator flux magnitude and the motor torque. The feedback values are estimated by processing the inverter dc-link voltage and the stator currents through the motor voltage model. Any error in the model parameter (i.e. the stator resistance) and in transducing voltage and currents yields an incorrect estimation of the controlled variables, thus altering the drive operation. In this paper the various errors are considered and their effect on the drive operation is studied analytically. The study shows that some errors lead to instability of the drive whilst some others deteriorate its steady-state performance. The theoretical findings are substantiated by experimental results.

[1]  Marian P. Kazmierkowski,et al.  Direct torque control of PWM inverter-fed AC motors - a survey , 2004, IEEE Transactions on Industrial Electronics.

[2]  M. Depenbrock,et al.  Direct self-control (DSC) of inverter-fed induction machine , 1988 .

[3]  Byeong-Seok Lee,et al.  Adaptive stator resistance compensator for high performance direct torque controlled induction motor drives , 1998, Conference Record of 1998 IEEE Industry Applications Conference. Thirty-Third IAS Annual Meeting (Cat. No.98CH36242).

[4]  Toshihiko Noguchi,et al.  A New Quick-Response and High-Efficiency Control Strategy of an Induction Motor , 1986, IEEE Transactions on Industry Applications.

[5]  Pasi Pohjalainen,et al.  The Next Generation Motor Control Method: Direct Torque Control (DTC) , 1995 .

[6]  D. S. Zinger,et al.  PI and fuzzy estimators for tuning the stator resistance in direct torque control of induction machines , 1994 .

[7]  P. Tiitinen,et al.  The next generation motor control method, DTC direct torque control , 1996, Proceedings of International Conference on Power Electronics, Drives and Energy Systems for Industrial Growth.

[8]  J.N. Nash.  Direct torque control, induction motor vector control without an encoder , 1996, Conference Record of 1996 Annual Pulp and Paper Industry Technical Conference.

[9]  Seung-Ki Sul,et al.  Analysis and compensation of current measurement error in vector controlled AC motor drives , 1996, IAS '96. Conference Record of the 1996 IEEE Industry Applications Conference Thirty-First IAS Annual Meeting.